1.5

1.5

public class stringcompress{
	 
    public static void main(String[] args)
    {
        String test = "aaabbccddaaaaaabba";
        String result = compress(test);
        System.out.println(result);
    }
    
    public static String compress(String s)
    {
        if(s.equals(null))
        	return null;
        
        if(s.length() <= 2)
        	return s;
            
        int length = s.length();
        char cur = s.charAt(1);
        char pre = s.charAt(0);
        int count = 1;
        String result = s.substring(0,1);
        
        for(int i = 1; i < length; i++)
        {
            cur = s.charAt(i);
            if(count == 0)
            {
                result = result.concat(Character.toString(cur));
                count++;
            }
            
            if(cur == pre)
            {
                count++;
                pre = cur;
                if(i == length - 1)
                	result = result.concat(Integer.toString(count));
            }
            else
            {
                result = result.concat(Integer.toString(count));
                count = 0;
                pre = cur;
                if(i == length - 1)
                {
                	result = result.concat(s.substring(i,i+1));
                	result = result.concat(Integer.toString(1));
                }
            }
        }
        
        if(result.length() >= s.length())
            return s;
        else
            return result;
    }
}